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Jan 2017

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1

Emerson Sensi UP500W Thermostat Installation Issue

Hello. I am looking for some ideas on why after I installed my new Emerson UP500W thermostat my AC will not cool. The fan kicks on and air flows but it is not cold air. The heat pump does kick in and puts out hot air. I called Sensi support and they confirm all my wires and setting are what they say they should be so they are a dead end for my issue. I have a Lenox 14HPX-048-230 single heat pump system. Attached is a picture of my old thermostat wiring system a S1-THEU21P7S and The wiring of my new Sensi UP500W thermostat as guided by Sensi support. On the Sensi thermostat setup the outdoor setting is HP1, the indoor setting is on EL2 and I tried both o and b settings in the options menu. Any ideas would be greatly appreciated.

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Feb 2012

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1,797

You could try to reinstall your existing thermostat to see if it still controls the system properly. You could also try removing the red, yellow, orange and green wires from the thermostat and join them together. With these wires join together the system should run in the cooing mode. Most heat pump system are set up to run in cooling with the reversing valve (orange wire) energized a few are not setup this way. If your system runs in the heating mode with these wires joined together remove the orange wire and just leave the red, yellow and green wires join together. If your system runs in the heat mode with the orange wire joined or not joined you most likely have a issue with the reversing valve. Make sure that when you remove the wires that you turn the power off to the HVAC system. Make sure that when the power is on that do not let any of the wires touch the C wire.